Level.



No. 892,353. PATENTED JUNE 80, 1908.

R. s. BLAIR.

LEVEL.

APPLICATION FILED FEB. 5. 1908.

FIGJ. 7 9

l 8 no.2.

FIG.3.

FNLS.

W/ TNE SSE S 6 gmgyro/1 UNITED STACEFLS PATENT OFFICE.

ROBERT S. BLAIR, OF NEW ROCHELLE, NEW YORK.

. lines and the like.

One of the objects is to provide a practical and efficient device of the above nature which shall give an indication which is readily and quickly visible under'all working conditions.

Another object is to provide an eflicient level which shall be sensitive of indication and yet give quick results.

Other objects are to provide devices of the above nature which shall be cheap, reliable and durable and shall stand hard handling and severe weather conditions without serious impairmentof efficiency.

Other objects will be in part obvious and I in art pointed out hereinafter.

he invention accordingly consists in the features of construction, combinations of elements and arrangement of parts which will be exemplified in the construction hereinafter set forth, and the scope of the a plica tion of whiclrwill be indicated in the ollowing claims.

Inthe accompanying drawing, wherein is shown one or more of various possible embodiments of the several features of this invention, Figure 1 is 'a side elevation of one of the same. Fig. 2 is a lan thereof. Fig. 3 is a plan of a slightly difierent form of tube. Fig. 4 is a side elevation of another level. Fig. 5 1s a plan of the same. F1 6 1s a sectional view taken along the line f-X of Fi 4. Fig. 7 is a similar view showing a different form of light divertin means. Fig.

8 is a similar view showing fiie application of protective devices. -Fig. 9 is .a lan of another form of level. Fig.'' 10 is aside elevation thereof.

Similar reference characters refer to similar parts throughout the several views of the drawing.

In order to render certain features more readily and fully understood, it may here be noted that in the use of leveling devices of Specification of Letters Patent.

Application filed February 6, 1908.

. Patented June 30, 1908.

Serial No. 414,294.

various types, it is often difficult to read the dark locations in which the work must be carried on.. It is, however, often of 'rime importance that the work be qfiiick ycarried on, and hence the instrument s ould not only should preferably-be rapid in action. It is, of course, desirable, 'however,'that the inment sensitive in action.

The above and other desirablefeatures are attained without. resultant disadvantages in constructions of the nature ofthose hereinafter'set forth.

ing, there is shown in Fig. 1 a tube or receptacle 1 mounted in a block 2 or other desired form of ,mounting. It is to be understood herein the same are somewhat diagrammatically indicated, and the invention 18 susceptible of application in devices having mount- 1 is slightly convex throughout a considerable portion of its length as at 3, and the ends thereof are preferably downwardly turned as at 4, being more sharply convex and may be set in the mounting. 2 as by laster or any tube 1' is very slight in a longitudinal-direction, and, in fact, may be almost straight in the most sensitive levels.

Tube or receptacle-1 is nearly liquid 6, as mercury, and a portion of the remaining s ace is occupied by another liquid 7, prefera 1y colored alcohol. These li uids are so proportioned anddisposed, an the tube'so formed, as preferably to leave a hub ble 8 which extends substantially through surface'of the mercury to reflect ight upwardly at this point. In this manner the bubble is quickly discernible, not only by the contrast in color, but by the reflected light from the surface of the mercury atthe bubble 8. These fluids are not onl of different s ecific gravities, but are se -se arating.

quickly se arate' into superposed layers or strata, an it may here be noted that the term self-separatin as used throughout this descri tron an the following claims is intende to denote such'a quality or characteristic It may also be noted at this point thr indication of level, as on dark days and in be of a nature permitting quick re'a ding,but

dications should be'accurate and the instruthat with respect to the mountings shownin s or supports of various types. The tube the fluid 7, and thus permits the bri ht upper Referring now-to the accompanying drawother desired means. --It is to e. understood that the convexity of the upper 'wall of the I 9Ov filled With'a hat is, upon being shaken toget er they is thus indicating byits position, ,that isthe"- position of the'liquid which forms it, the po-- terms of thenature ofi1pper and lower:

refer to" the-normal-operat'ive position of the instrument, and that by'the term convex,

' as used with reference to a wall or other ele ,ment is meant that its under surface is rounded upwardly. so as .to be slightly hollowed or concave ifviewed from beneath.

The operation and use 'of'the above de-' scribed embodiment of thisinven'tion is sub-.

and-mounted asshown, .the flu1d' 7 11s' in a po' stant'ially as follows: With the tube filled .sition above the fluid-6, and the bubble-'8 oc-- oupies the up ermost position of-the tube or receptacle 1-, ue, of'course, to the fact, that it seeks the highest pointof the receptacle,

sition or inclination of the receptacle If,

then, it be desired to adjust a membef'untilv it be level, the mounting 2 is placed u on the" same and the-member swunguntilt ,e' bubble comes opposite a roper ndicating mark as at 9 at the center the instrument, whereuponthe member is level. 3 The-mercury 6,

'55 pronounced toward the edges ofthe instru surface into levelposition. "1 1 is filled with the heavy fluid 12- and lighter v by reason-of its weight, quickly changes its position and. tends to carry the lighter fluid 7. as a WlZlOlG, and in this lighter fluid the bu'bble' Siinds the highest point. i This results in;

a quick action of the instrument, and the contrast and other features above noted permit the ready observation of its indication under all conditions of-use' vIf desired, the lighter fluid'may be small in amount, whereu on'it will form a ring about the .bubble as indicated at 10 in Fig. 3 of the drawin s, and if the bubblebe small, this ring will form in itself an indicating means. It is to be noted in connection withthis type of instrument, as wellas that first-described, that the lighter fluid tends to spread out between the mercury and the upper wall of they tube or receptacle and act as a lubricant to permit a more ready action of the heavier.

uid A In Figs. 9 and 10 is indicated theso called watch crystal type of level in which the receptacle or holder 11 is substantially circular and equally rounded in all direct-ions,- thus indicating the precise direction'in which adjustment is required, in order to bring the This receptacle fluid '13 in a manner substantially identical with the filling of the tubular receptacle first described. The curvature prefera 1y is more ""ment as at 14, in order to do away with any tendency of the bubble to stay at the edges of the instrument.

.there is provided a type of instrument in.

It will thus be seen that which the objects 6f this invention are achieved, and the above enumeratedadvantages are'among others present. By the. use ofaplurali'ty of fluids, I attain'a more efficient action, irrespective of the contrast mirrors. 21,- best shown 'in Fig. 6of the drawings.) Thesemirrors act to divert therays of bersZA are provided at each side of the tube,

. ceases of color; and by the use of fluids of contrasting colors, and more particularly a substantially opaque fluid, as colored alcohol, used inconnection with av reflecting medium, as

the upper surface'of the mercury, the posi-' tion of the rece tacle, by-whichis mea'ntthe levelness or lacif of levelness of the memberwi'th-which it is used, is quickly. indicated;

. In Fig. 4' of 'thexdrawingszis shown a slightly different ty e of instrument in which the. tube 1.5 is. fille partially I with a trans parent fluid 16 as caibOri-bisulfid '(CS "and the upper fiuid-.1 7-may be; as before coloredalcoh which is relatively opaque and is" self-separating with respect thereto. 'Thebubble '18 preferably extendssubstantially .through the alcohol, and the mounting-19 in which the tube is positioned is cut away as at 20, and is'provid'e d oppositely inclined ;light,"'indicated at 22,' and throw the same against the lower wall of'the tube 15. this manner the-bubble is brightly 'illumi-- nated by the light thrown through the car- 9.9 bon-bisulfid,-and the indication the instrument quickly read. i

In Fig. 7 s shown-a cross-section of a de vice similar tothat of Fig. 6, the same employing refracting prisms 23- instead of the mi1 -rors, and itis to be understood that, if desired,'reflecting risms or other means ma be employed for ecting the light throug 1 i the carbon-bisulfid. In fact, certainof the advantageous features of; this invention may 109 be acln'evedjby silvering the surface of the lower wall of the receptacle; i

In Fig. 8 is shown a device 'similar to Fig. 6; with the exception that protective mem-- and are formed with openings 25 therein to admit the light to the mirrors. Certainbroad features of the constructions 4 1 employing the carbon-bisulfid are obviously common to thejform of instrument fir'st-de- 113 scribed, although'theformer instrument, as well as the latter, each possess advantages peculiar to itself.

It will thus be seen'that' there are set forth forms of instruments of simple, cheap and 115 durable construction, which are sensitive and reliable in indication, and which, among other advantagesalready set forth, are susinvention what I 130 mally extending substantialy fromend to vend thereof, and a liquid of darker appearance or color upon sai first liquid and at apted by its appearance to indicate the position ofsaid tube. I 2. A level tube having therein a liquid normally extendin substantially from end to end thereof, ant a second liquid-of contrasting color or a earance resting upon said first liquid,'sai(i liquids being so disposed and proportioned as to form a bubble of an appearance readily distinguishable from said second li uid and adapted to indicate by its position t e position of said tube.

3. Inlevel construction, in combination, a

receptacle provided with a convex upper wall and a lower wall directly beneath the same, a

body of mercury upon said lower. wall and between the same and said upper wall and nearl filling said receptacle, and a lighter liqui extending between said mercury and said upper wall and acting to permit a more ready action of said mercury, said liquids forming a bubble by which the position of v said receptacle is indicated.

q 4. In level construction, in combination, a receptacle provided with a convex upperwall and a lower wall directly beneath the same, a liquid upon said lower wall and between the same and said up er wall, and a second liquid resting upon saufhirst liquid and so disposed and proportioned as to indicate by its osition the position of said receptacle, sai liquids being self-separating.

- 5. In level construction, in combination, a receptacle provided with a convex upper wall and a lower wall directlybeneath the same, a liquid upon said lower wall and between the same and said upper wall, and a liquid of a darker color or appearance resting upon said first liquid and so disposed and proportioned vided with a convex u per wall and a lower color wall directly beneath t 1e same, a liquid upon said lower wall and between the same and said u er'wall, and a second liquid of. a

diiferent from that of said first liquid resting upon said first liquid and so disposed and proportioned as to form a line of division with said first liquid visible through said upper wall, and indicate thereby the position of the receptacle.

7. A device of the class described, comprising a mounting and a level tube fixed upon said mounting and having therein a liquid normally extending substantially from end to end thereof, and a second liquid of contrastin color or a pearanc'e resting upon said first iquid, sai liquids being so disposed and proportioned as to form a bubble of an a' pearance readily distinguishable from sai second liquid and adapted to indicate by its position the levelness of a surface upon which said mounting is placed.

8. In level construction, in combination, a receptacle provided with a convex upper wall and a'lower wall directly beneath the same, a

liquid upon said lower wall and between the same and said upper wall, and a second liquid self-separating with res ect to said first liquid and resting upon sair first liquid and so disposed and proportioned as to form a bubble extending substantially to the surface of said first liquid and ada ted to indicate by its position the position 0 said receptacle.

9. In level construction, in combination, a receptacle provided with a convex upper wall and a lower wall directly beneath the same, a liquid upon said lower wall and between the same and said upper wall, and-a second liquid self-separating with res ect to said first liquid and resting upon said first liquid and so disposed and proportioned as to form a bubble extending substantially to the surface of said first liqxuid and adapted to indicate by its position t e position of said receptacle, sait li uids being of different colors.

10. In-level construction, in combination, a receptacle provided with a convex upper wall and a lower wall directly beneath the same, a body of mercury upon said lower wall and between, the same and said upper wall; and a lighter liquid resting upon said mercury and so disposed asto form a bubble extending substantiallv to said mercury and adapted to indicate by its position the position of said receptacle.

11. 111 level construction, in combination,

a receptacle provided with a convex upper wall and a lower wall directly beneath the same, a body of mercury upon said lower wall and between the same and said upper wall, and a lighter liquid-resting upon said mercury and so disposed as to form a bubble extending substantially to said mercury and adapted to indicate by its position the osition of said receptacle, said second 'liquir being of a contrasting color with respect to said mercur 12. l ii level construction, in combination, a receptacle provided with a convex upper wall and a lower wall directly beneath the same, a liquid upon said lower wall and be-v tween the same and said upper wall,-and a second liquid self-Se arating with respect to said first liquid am resting upon said first liquid and so disposed and proportioned as lighter fiuid substantially opaque and of'a to a point above the different colorfrorn said liquid and floating thereon beneath said upper wall,..'whereby the contrasting line between said liquid-and said li hter fluid is visible through said upper We 1 and is adapted toindicate the position of said receptacle.

14. A level tube with a liquid therein forming a bubble to indicate the osition of the tube, and'me ans presenting a b face extending to a point above the lower portion of the tube and immediately bebright appearance and is 15. A level tube with a substantially opaque colored liquid therein formin abubb eito indicate the position of the tu e, and means presenting a bri ht surfaceextending lower ortion of the tub'e'land immediately bneat said bubble,

and liquid whereby said bubble is given a bright appearance and is readily distin able from surrounding portions of said l quid. 16. In level'construction, in combination, a receptacle having an upper .wall slightly convex in its central portion and more sharply convex at portions remote from the center, a liquid in said receptacle, and a lighter liquid in said receptacle and resting upon said first liquid, said liquid; being adapted by their position to indicate the position of said receptacle. v V

1 7. In level construction, a receptacle having an upper wall slightly convex in the central portions thereof and more sharply con vex at portions. remote from thetcenter, a'

body'of mercury-in said receptacle, and a lighter liquid in said receptacle restin upon said mercury, said mercury and said lighter liquid being adapted by their position to indicate the position of saidreceptacle.

18. In level construction, a-receptacle having an upper wall slightly. convex in the central portions thereof and more sharply convex at port-ions remote from the center, a body of mercury in said rece tacle, and a lighter liquid of contrasting color in said receptacle resting upon said mercury, said mercury and said lighter liquid being adapted by their position to indicate the position of said receptacle.

19, Inlevel construction, a tube slightlyconvex at the center and more sharply con- 1 said first right sur and liquid whereby said ish- ' extending substantially from one end to the vex at its ends, a'liguid in said tube, and a lighter li uid in sai .t'ube'andiresting upon by their position to indicate the position of.

said tube.

20. In level construction, combination, a tube having downturned end portions, a

- body of mercury within said tube and extending from end to end thereof, and a lighter-.1 liquid within" said tube resting upon said mercury and adapted to indicate by its position the position of said-tube.

quid, said'liquids being adapted 21. A level tube 'having'a'liquid therein extending substantially from one'end to the other thereof, and a second'and lighter liquid Within saidtube floated upon said first liquid I and-so proportioned as to form a bubble visible through said tube whereby, as the inclination of said tube is changed, said first liquid carries said second liquid toward one or the other of the ends of the tube and said bubble moves with saids'econd liquid itself therein to its highest point. I p 22. A level tube having a liquid therein other thereof, and a second liquid of adarker color and lighter weight withinsaid tube fio'ated upon said first'liquid and so proportioned as. to form a bubble visible through said tube and readily distinguishable from the surrounding liquid-whereby, as the inclination of said tube is changed, said first liquid: carries said second liquid toward one or the other of the ends of the tube and said bubble moves with said second liquid and adjusts itselftherein to its highe'st point. p

'23. 'A substantially straight level tube having a liquid therein extending substantially and adjusts I from endto endthereof and having floated upon said liquid and visible throu h the upper Wall of the tube a substantially opaque" substance of contrasting appearance .With respect to said liquid, and substantiallysu roundedby said liquid and freely movable lengthwise-ofithe tube whereby the position of the tube is indicated by the position of said substance therein, and "whereby said sub stance is readily distinguishable throughsaid upper wall by its contrast with said liquid.

In testimony whereof I affix my signature,

in the presence of two Witnesses. L

ROBERT. S BLAIR; Witnesses: i I

C. CoRsoN, B. (Jonson, 

